Eduardo Massaharu Aoki

Comparison of the diagnostic performance of panoramic and occlusal radiographs in detecting submandibular sialoliths.

Purpose The aim of this study was to assess and compare the diagnostic performance of panoramic and occlusal radiographs in detecting submandibular sialoliths. Materials and Methods A total of 40 patients (20 cases and 20 controls) were included in this retrospective study. Cases were defined as subjects with a submandibular sialolith confirmed by computed tomography (CT), whereas controls did not have any submandibular calcifications. Three observers with different expertise levels assessed panoramic and occlusal radiographs of all subjects for the presence of sialoliths. Intraobserver and interobserver agreement were assessed using the kappa test. Sensitivity, specificity, accuracy, positive and negative predictive values, and the diagnostic odds ratio of panoramic and occlusal radiographs in screening for submandibular sialoliths were calculated for each observer. Results The sensitivity and specificity values for occlusal and panoramic radiographs all ranged from 80% to 100%. The lowest values of sensitivity and specificity observed among the observers were 82.6% and 80%, respectively (P=0.001). Intraobserver and interobserver agreement were higher for occlusal radiographs than for panoramic radiographs, although panoramic radiographs demonstrated a higher overall accuracy. Conclusion Both panoramic and occlusal radiographic techniques displayed satisfactory diagnostic performance and should be considered before using a CT scan to detect submandibular sialoliths.

Osteoporotic alterations in a group of different ethnicity Brazilian postmenopausal women: An observational study

OBJECTIVES To compare peripheral bone mineral density alterations among Brazilian postmenopausal women from three ethnic groups considering age and body mass index influence; to correlate their bone mineral density with the mandibular cortical index (MCI); and to evaluate the influence of age, body mass index and ethnicity in the MCI using risk factor analysis. BACKGROUND Osteoporosis risk is known to have ethical influences. However, little is known about the differences in ethnicity in radiomorphometric indices. MATERIALS AND METHODS A total of 150 postmenopausal women with different ethnicities (Caucasian, Asian and Afro-descendant) who underwent peripheral dual X-ray absorptiometry and panoramic examination were included. Bone mineral density and MCI were assessed. Adjusted odds ratio analyses were performed on bone density and MCI considering the effect of age, ethnicity and body mass index. The correlations between the MCI and the dual X-ray absorptiometry results were made. RESULTS Old age, low body mass index and non-Afro-descendant were associated with low bone density. Compared with Afro-descendants, Asians and Caucasians have higher chances of having decreased bone mass. For the MCI, statistical analysis showed that age is the only variable associated with osteoporotic alterations in the mandible. Furthermore, an inverse correlation was found between the MCI and the T-scores. CONCLUSION Bone density is higher in Brazilian Afro-descendant women than in Caucasians and Asians. Patients age is associated with bone density and the MCI. The mandibular cortical index is inversely correlated with the peripheral densitometry results within the study ethnic population.

Assessment of alveolar bone marrow fat content using 15 T MRI

OBJECTIVES Bone marrow fat is inversely correlated with bone mineral density. The aim of this study is to present a method to quantify alveolar bone marrow fat content using a 15 T magnetic resonance imaging (MRI) scanner. STUDY DESIGN A 15 T MRI scanner with a 13-mm inner diameter loop-gap radiofrequency coil was used to scan seven 3-mm diameter alveolar bone biopsy specimens. A 3-D gradient-echo relaxation time (T1)-weighted pulse sequence was chosen to obtain images. All images were obtained with a voxel size (58 µm3) sufficient to resolve trabecular spaces. Automated volume of the bone marrow fat content and derived bone volume fraction (BV/TV) were calculated. Results were compared with actual BV/TV obtained from micro-computed tomography (CT) scans. RESULTS Mean fat tissue volume was 20.1 ± 11%. There was a significantly strong inverse correlation between fat tissue volume and BV/TV (r = -0.68; P = .045). Furthermore, there was a strong agreement between BV/TV derived from MRI and obtained with micro-CT (interclass correlation coefficient = 0.92; P = .001). CONCLUSIONS Bone marrow fat of small alveolar bone biopsy specimens can be quantified with sufficient spatial resolution using an ultra-high-field MRI scanner and a T1-weighted pulse sequence.

The use of a computed tomographic application for mobile devices in the diagnosis of oral and maxillofacial surgery.

AbstractThe aim of the current technical report was to introduce a computed tomographic (CT) application for mobile devices as a diagnostic tool for analyzing CT images. An iPad and an iPhone (Apple, Cuppertino, CA) were used to navigate through multiplanar reconstructions of cone beam CT scans, using an application derived from the OsiriX CT software. Tools and advantages of this method were recorded. In addition, images rendered in the iPad were manipulated during dental implant placement and grafting procedures to follow up and confirm the implant digital planning in real time. The study population consisted of 10 patients. In all cases, it was possible to use image manipulation tools, such as changing contrast and brightness, zooming, rotating, panning, performing both linear and area measurements, and analyzing gray-scale values of a region of interest. Furthermore, it was possible to use the OsiriX application in the dental clinic where the study was conducted, to follow-up the analyzed implant placement and grafting procedures at the chairside. The current findings suggest that technological and practical methods to visualize radiographic images are invaluable resources to improve training, teaching, networking, and the performance of real-time follow-up of oral and maxillofacial surgical procedures. This article discusses the advantages and disadvantages of introducing this new technology in the clinical routine.

Ultrasound analysis of mental artery flow in elderly patients: a case–control study

OBJECTIVES Mental artery flow decreases with age and may have an aetiological role in alveolar ridge atrophy. The aim of this study was to identify factors associated with alterations of mental artery flow, assessed by ultrasonography. METHODS This case-control study was conducted on elderly patients (aged above 60 years) at the beginning of dental treatment. Intraoral B-mode Doppler ultrasonography was used to assess mental artery flow. The cases were defined as patients with a weak/absent ultrasound signal, whereas the controls presented a strong ultrasound signal. Demographics and radiographic findings (low bone mineral density on dual-energy X-ray absorptiometry and mandibular cortical index on panoramic radiographs) were analysed as risk factors for weak/absent ultrasound signal and were calculated as adjusted odds ratios (AORs) with 95% confidence intervals (CIs) using conditional logistic regression. In addition, the Students t-test was used to compare the mean alveolar bone height of the analysed groups. A p-value <0.05 was considered statistically significant. RESULTS A total of 30 ultrasound examinations (12 cases and 18 controls) were analysed. A weak/absent mental artery pulse strength was significantly associated with edentulism (AOR = 3.67; 95% CI = 0.86-15.63; p = 0.046). In addition, there was a significant difference in alveolar bone height between edentulous cases and controls (p = 0.036). CONCLUSIONS Within the limitations of this study, the present results indicate that edentulism is associated with diminished mental artery flow, which, in turn, affects alveolar bone height.